posted on 2014-02-07, 00:00authored byChao Du, Jun-Rong Liang, Dan-Dan Chen, Bin Xu, Wen-Hao Zhuo, Ya-Hui Gao, Chang-Ping Chen, Chris Bowler, Wen Zhang
Silicon is a critical element for
diatom growth; however our understanding
of the molecular mechanisms involved in intracellular silicon responses
are limited. In this study, an iTRAQ-LC–MS/MS quantitative
proteomic approach was coupled with an established synchrony technique
to reveal the global metabolic silicon-response in the model diatom Thalassiosira pseudonana subject to silicon starvation and
readdition. Four samples, which corresponded to the time of silicon
starvation, girdle band synthesis, valve formation, and right after
daughter cell separation (0, 1, 5, 7 h), were collected for the proteomic
analysis. The results indicated that a total of 1,831 proteins, representing
16% of the predicted proteins encoded by the T. pseudonana genome, could be identified. Of the identified proteins, 165 were
defined as being differentially expressed proteins, and these proteins
could be linked to multiple biochemical pathways. In particular, a
number of proteins related to silicon transport, cell wall synthesis,
and cell-cycle progress could be identified. In addition, other proteins
that are potentially involved in amino acid synthesis, protein metabolism,
and energy generation may have roles in the cellular response to silicon.
Our findings provide a range of valuable information that will be
of use for further studies of this important physiological response
that is unique to diatoms.